Accom ASWR8150 Technical Manual page 56

Signal Chassis Connections
Vertical Blanking – Frame Delay Output Module
There is a control for vertical output blanking in the Engineering menu
Output submenu. You can individually blank or unblank the first active
line and the previous nine lines of each field. In the 525-line standard,
you can blank/unblank lines 12 through 21 and 275 through 284. In the
625-line standard, you can blank/unblank lines 15 through 24 and 327
through 336.
Press the V Blanking softkey to access the controls for independently
blanking or unblanking any of these lines. The Blanking Status
pushknob label indicates which lines are blanked by displaying the line
number with its two digits oriented vertically. In 525-line systems, the
display looks like this:
In 625-line systems, the display looks like this:
The dashes (--) are "place holders" for the other lines that are currently
unblanked. To change the blanking status of any line (plus its
counterpart in Field 2), use the Select Line pushknob to select the line
number whose blanking status you want to change, then press the V
Blanking softkey. This toggles the Blanking Status display to add that
line number if it was not present, or to remove it if it was present. The
corresponding line in Field 2 is also blanked or unblanked accordingly.
Output Bit Resolution
The 8150 maintains full 10-bit processing throughout. However, if you
feed its output to a device that accepts or processes only eight bits, you
can configure the digital outputs to avoid banding and other truncation
errors. (The analog monitor output always uses a 10-bit signal in its
digital-to-analog conversion, and is not affected by this setting.) In the
Engineering Output submenu, the Bits softkey toggles the following. 10
(the default setting) keeps the full 10-bit resolution of the internal
processing. 8 Rounded takes the two least significant bits (LSBs) of the
10-bit signal and rounds them down to the next lower 8-bit value if the
binary value of the LSBs is 01. It rounds them up to the next higher 8-bit
value if the binary value of the LSBs is 11. It randomly rounds them down
2-16
Installation
on the Program bus. Observe the program output on a
waveform monitor, and verify that the correct lines are
blanked or unblanked as needed.
11111111--
23456789--
11111222--
56789012--
8150 Technical Guide
9100-0212-04 - May 2000